A 2003 article in the Military Review has proven darkly prescient with last weekend’s terroristsiege of an indoor shoppingmall in Nairobi, Kenya. Written by two retired U.S. Army Lieutenant Colonels, the piece outlines the emergence of modern-day siege warfare tactics, or the invasion of large architectural structures.

In the magazine's September/October 2003 issue, Lester W. Grau and Geoffrey Demarest collaboratively warned that, “while perhaps not a likely target in a traditional military sense, an indoor shopping mall could be attractive as a terrorist target.”

Their article goes on to imagine what might happen when armed groups lay siege to megastructures—prisons, malls, airports, embassies, cinemas, skyscrapers, even entire gated subdivisions—asking, in the process, how we might protect ourselves when acts of war or terrorism erupt in the midst of our everyday, civilian environments.

The disturbing realization is that, for the U.S. Army, the vulnerable targets of tomorrow are shopping malls and schoolyards, airports and sports stadiums, perhaps even suburban streets. The mall siege in Nairobi is perhaps only the most recent, horrifying example of how this will look.

For the most part, however, the recommendations of the Military Review remain on the side of armed fantasy; the authors even refer to these structures as "Die Hard buildings," as if in a wink and a nudge to watching too many action movies, and their advice, for the most part, remains abstract and highly general. But their conclusion is straightforward enough: any building can be inverted or, in a sense, turned against the people who try to attack it, and this can be done by way of the architecture itself. You can tactically misuse the building, so to speak, to hide from or, even better, to trap and bewilder your assailants.

Recall, for example, that, amongst the many terrifying stories emerging from the Nairobi mall, we learned that some people survived by climbing into ventilation shafts and HVAC ducts to hide. This was perversely mirrored by the attackers themselves, who equally misused the building for their ends. "The building’s blueprints were studied, down to the ventilation ducts," the New York Times reports. Further, a few days before the siege, "powerful belt-fed machine guns were secretly stashed in a shop in the mall with the help of a colluding employee."

Grau and Demarest go on to explain, indoor malls are already designed to manipulate human movement—“Planners design malls to move people slowly past a wide display of consumer goods while deterring theft," they write—so it is simply a question of accentuating or amplifying this tendency for tactical reasons, pushing certain users out like a splinter from skin or isolating them in tightly controlled dead ends. Here, the authors refer to the design of “circuitous paths," or routes of circulation that do everything but offer "a straight passage to the mall's main area." The mall, in this reading, is a labyrinth disguised as a retail space, filled with constrained halls and corridors that, if used aggressively, can confuse and strand potential adversaries.

The retired Lieutenant Colonels leading us through this thought-exercise point out the obvious: that storefront gates can be closed automatically on a moment's notice, that elevators and escalators can be turned off or reversed, and that the limited passageways through which movement is channeled can be blocked off entirely. Guards, they suggest, "can seal intruders into a holding area that appears to be a normal lobby.” Meanwhile, in a feature that would be as useful for chasing teenage shoplifters as for confronting terrorists, “if troublemakers try to exit the mall in a hurry, they must thread a circuitous path to get out. Mall parking lots, designed to impede a quick getaway, funnel traffic to a few exits, which police cars can reach rapidly.”

In any case, the sad and obvious reality of all this is that, if you are not in what amounts to a permanent state of readiness for such an attack—if you have not, in effect, militarized every shopping mall—then there is very little you will be prepared to do in response. The siege in Nairobi has made this all too tragically clear.

At an Army Reserve base in New Jersey, soldiers practice "entering a building, clearing a room, and engaging targets during urban operations." Photo courtesy U.S. Army.

At least part of the reason for this is that military plans for storming and re-taking densely populated civilian structures such as shopping malls—that is, laying siege to architectural megastructures—have few opportunities for realistic training and practice. Full-scale trial runs, for instance, of violent mall-clearing exercises featuring hundreds of panicked civilians would be nearly impossible to coordinate, and the risks of revenue loss or even physical damage to the buildings themselves are both obvious and hard to avoid.

Briefly, consider other controversial examples of military training in civilian locations, such as the series of late-night military helicopter exercises held in downtown Los Angeles back in 1989. This involved full-scale trials of “urban approach and departure techniques” over high-rise apartments and office buildings in the business district—something repeated in 2009 with Blackhawk pilots flying through the city on summer evenings, intended "to familiarize military personnel with urban settings and prepare them for future assignments overseas.”

More exercises like these would clearly boost the readiness of military forces and police first-responders, but how far do we want to go risking near-total militarization of our cities in the name of personal safety?

There was a lot of talk last year about an abandoned big box store in Texas that had been gut-renovated and transformed into a public library. It is by no means difficult to imagine a slightly different fate for that big box store, or for any of the nation’s many dead malls: being transformed instead into a kind of counter-terrorism training center for urban warfare, where soldiers and police can learn how to resist modern siege tactics using the same guidelines outlined by the Military Review in 2003.

The goal cannot be to militarize civilian architectural space by infesting our everyday environment with control technologies, or by simply turning city planning and the management of public space over to the Army; nonetheless, it seems smart to recognize that the architectural circumstances of war have changed, and that schoolyards, shopping malls, sports stadia, and even the suburbs are doomed to experience horrific, organized violence. Somehow preparing for this fate, without over-fortifying ourselves into self-imposed "Die Hard buildings," is one of the dark requirements of architects and security planners in the years to come.